Crosswind Landings / "Impossible Landing" TE / Crosswind landing advice
-
I thought that is what most aircraft do on approach due to ground effect.
Ground effect only occurs when your height above ground is equal to or less than your aircraft’s wingspan. So in an F-16 you would have to be around 30ft off the ground to experience ground effect.
-
After touchdown, perform two-point aerodynamic braking
using the rudder to maintain aircraft track down the run-way and
flaperon to prevent wing rise. In crosswinds, the
aircraft may drift downwind due to side loads imposed by
the crosswinds or travel upwind due to insufficient di-rectional
control inputs/availability.…
With all LG on the run-way, maintain
directional control with rudder, differential
braking, and NWS if required.
During landing rollout, the main concerns are wing rise
(roll control), weathervaning (directional control), and
downwind drift. Wing rise is controlled by flaperon into
the crosswind. Excessive flaperon deflection degrades di-rectional
control. Use rudder and differential braking to
control ground track, especially on wet or icy runways.
Engage NWS if required to maintain directional control
and to prevent departure from the runway.Sounds like every other flight manual I’ve read. The only thing I can find are (supposed) pilots saying the aircraft waddles down the runway when landed in a crab, and it doesn’t waddle/bounce as much if you kick out of the crab before touchdown.
http://www.f-16.net/f-16_forum_viewtopic-t-9288-start-0.html
Are there any data available on the dynamics of crosswind f16 landings? I’d like to see some.
-
There is an series of articles I always refer to from codeone magazine called “Semper Viper” where is a very good article about landing cross wind. If you can find it online it will say the same thing Dee-Jay and all the guys have been saying.
-
-
This seems to be unique to the f16. Are there any other aircraft that right themselves while landing in crosswind? In BMS just now, landing in a 15 knot crosswind from left to right, the aircraft yawed itself to the right, while the rudder went hard left to try to arrest the yaw.
I’m just wondering what in the design makes it different.
-
This seems to be unique to the f16. Are there any other aircraft that right themselves while landing in crosswind? In BMS just now, landing in a 15 knot crosswind from left to right, the aircraft yawed itself to the right, while the rudder went hard left to try to arrest the yaw.
I’m just wondering what in the design makes it different.
Juts my opinion, the landing gear. The way they landing gear compress, etc. Part of it. Aerodynamics and other things come into play.
-
Wish I knew about this when looking for a project in my stability and control class. heh.
-
This seems to be unique to the f16. Are there any other aircraft that right themselves while landing in crosswind? In BMS just now, landing in a 15 knot crosswind from left to right, the aircraft yawed itself to the right, while the rudder went hard left to try to arrest the yaw.
I’m just wondering what in the design makes it different.
not really unique… you get a similar reaction from an evektor sportstar LSA. of course, you will also likely pull tyres off too, and it wont be as violent…
the main gear are aft of the CoG. they also have a fair amount of friction - loads more if they are not aligned with the direction of travel.
the momentum is forwards, and that will want to drag the gear as the point of contact behind the CoG relative to the direction of movement…
the rudder part is due to the FLCS, but the rapid yaw right is more than I would expect to see if both gear touch down simultaneously.
I dunno. I started out thinking it wasnt a massive difference, but now that I reflect, it is a fairly violent maneuver (in BMS).
-
This seems to be unique to the f16.
Absolutely not. Same on Mirage2000, Rafael, certainty on F22, Typhoon etc … And (IIRC) on
(not 100% sure)EDIT:
For A380:
-
Absolutely not. Same on Mirage2000, Rafael, certainty on F22, Typhoon etc … And (IIRC) on
(not 100% sure)EDIT:
For A380:
And the space shuttle it’s pretty much standard landing for every FlyByWire aircraft…
-
For Duck Hawk:
-
Can someone tell me what the chime is @ 20 sec?
-
-
This seems to be unique to the f16. Are there any other aircraft that right themselves while landing in crosswind? In BMS just now, landing in a 15 knot crosswind from left to right, the aircraft yawed itself to the right, while the rudder went hard left to try to arrest the yaw.
I’m just wondering what in the design makes it different.
I already answered to that argument.
Flcs has nothing to do with this. This is just basic physics, the friction on gear and the fact wheel can only rotate around 1axis forces the AC to align on its velocity vector. The torque generated is a function of tire friction which is dependant on tire rubber / runway/ weight on wheel, tire pressure.
All AC in the world have this, of course a A380 is less sensitive because yaw inertia is too much important.
I can’t say if the BMS behavior is too much or not as so many parameters enter in the game here. I would need to land a f16 myself to judge
However it has nothing to do with FLCS, the rudder effect is just a consequence of the physical effect not the cause
-
yay I was right
-
the main gear are aft of the CoG. they also have a fair amount of friction - loads more if they are not aligned with the direction of travel.
That makes sense, but there is more than just tire friction acting on an aircraft during a crosswind landing. The moment that the main gear provides is countered by the weathervane effect of the aircraft. You still need some rudder to keep the plane from turning into the wind.
I dunno. I started out thinking it wasnt a massive difference, but now that I reflect, it is a fairly violent maneuver (in BMS).
It might be exaggerated a bit. Maybe its not, since the plane is pretty small, heavy, and has a fairly high landing speed. Its not like I could say tho, the planes I’ve flown have a hard time cruising at its touchdown speed. The f16 video posted above does show a strong correction at touchdown, which looks similar to what we see in BMS.
Quote Originally Posted by starbird View Post
This seems to be unique to the f16.
Absolutely not. Same on Mirage2000, Rafael, certainty on F22, Typhoon etc … And (IIRC) on A380 (not 100% sure)The difference between what I see in BMS and that 380 landing is that the 380 needs a lot of rudder to decrab, where the BMS f16 needs no rudder at all (not just input, no rudder movement). But I do agree that the effect is correct.
-
hmm. with you on the difference between their VSO and our VNE!!!
I havent thought of it as need rudder for this, I think of it as keep it on the centerline. but yeah, they weathercock. hmm. I still dont think my friction Idea is that far off though. in BMS, you have a heavy plane, so it is less affected by weathercocking.
-
I expect the same answer but I got different answer from the pilot, he flies 1350 hours F-16A/B and said decrab was needed just before touchdown and the secondary effect of rudder (roll) was still small.
But maybe it’s because he flies the block 15. I don’t know about block 50. Just fyi…
-
@Duck:
But maybe it’s because he flies the block 15. I don’t know about block 50. Just fyi…
IMO, no big differences (or even no differences at all) between blk15 and 52 … but ?
-
**EDIT
Asked again … here is the right answer.**
@Duck:
But maybe it’s because he flies the block 15. I don’t know about block 50. Just fyi…
Welll … finaly … maybe!?..
I just have an answer from a MLU pilot … unfortunately … I’ve closed the Skype windows before having the time to note exactly what was the sequence of his response … but IIRC …
AAR: No.
Flight: No, not recommanded, forbidden sometimes (see -1)
Landing: no, no, no